Remove nuget.org spec from the repository

None of the recent maintainers has remembered trying to keep the
nuget.org package up to date.

As of writing this, it's over 7 years since the last mustache.js
version got published on nuget (v0.7.2).

Adding to that, there has been no questions asked from the nuget
community about outdated versions.

With the above in mind, we'll remove the nuget spec from our repo
since it only adds to confusion at this point.

Refs https://www.nuget.org/packages/mustache.js/

hooks/pre-commit

@@ -79,6 +79,5 @@ end
 
 bumper = Bumper.new([
 	Source.new('mustache.mjs', /version: '([^']+)'/),
-	Source.new('mustache.js.nuspec', /<version>([^<]+)<\/version>/),
 ])
 bumper.start

mustache.js.nuspec

@@ -1,14 +0,0 @@
-<?xml version="1.0"?>
-<package >
-  <metadata>
-    <id>mustache.js</id>
-    <version>4.1.0</version>
-    <authors>mustache.js Authors</authors>
-    <licenseUrl>https://github.com/janl/mustache.js/blob/master/LICENSE</licenseUrl>
-    <projectUrl>http://mustache.github.com/</projectUrl>
-    <requireLicenseAcceptance>false</requireLicenseAcceptance>
-    <description>Logic-less templates in JavaScript.</description>
-    <releaseNotes></releaseNotes>
-    <tags>mustache template templates javascript</tags>
-  </metadata>
-</package>